Implants are now the most popular means of replacing a lost tooth. Due to their relatively low maintenance and durability people are increasingly preferring implants to bridges. None the less, there is a largely undocumented body of complaints in the prosthetic manufacturer's literature, which is voiced to front line dentists about implants, by their patients. These complaints generally are about food impacting and accumulating around and beneath the crown portion of the implant in the enlarged embrasure between the implant and the adjacent teeth.
In current practice after a tooth has been removed, first i) an upright pilot hole which is centered in the opening left by the removed tooth, is drilled in the jaw, and then ii) a self-tapping retaining screw, having an upper internally threaded opening therein, is turned into the pilot hole, beneath the removed tooth. The top side portion of the retaining screw comprises a platform to which a crown prosthetic portion is subsequently attached thereon, utilizing the internally threaded opening in the top portion of the retaining screw. iii) After the retaining screw is inserted in the jawbone the gum is sutured closely around the top portion of the retaining screw. iv) Finally, the upper crown portion of the implant is cast to fit the opening between the adjacent teeth. The peripheral sides of the crown portion of the implant taper from the large generally rectangular upper crown portion to a base diameter which corresponds to the platform diameter of the retaining screw. Generally the upper crown portion is rectangular; generally the lower crown is round; and generally the diameter of the base portion is less than one half of the length of the rectangular portion.
This is the essence of the problem of impacting and accumulating trapped food. A tooth which was generally rectangular from top to bottom, has been replaced by a prostheses having a custom fitted generally rectangular upper crown portion, and a generally round bottom portion, sized not to even approximately fit the opening between the adjacent teeth, but rather extremely narrowed to seat on the top face of the retaining screw. The embrasures, the spaces between the implant and the adjoining teeth, has been multiply enlarged. Food packs therein, and it must be constantly, and inconveniently, removed to prevent gingival inflammation and gum infection. Patients have little option but to carry floss or a toothpick and remove debris after every time they eat.